1. Field of the Invention
The present invention relates to a quick connect/disconnect hose connector or coupling used for transferring liquefied gas fuel from a pressurized fixed or mobile storage tank, to a fuel tank for a vehicle or an appliance, or a stationary fuel tank.
2. Description of the Related Art
A number of vehicles, such as forklift trucks, operate on propane or other LP gas, which is stored in a fuel tank on a mobile vehicle. These fuel tanks require refilling periodically, which is typically from a large fixed or mobile storage tank. In a commercial operation for filling motor fuel cylinders with LP gas or propane for forklift trucks, for example, a fuel distribution center may fill up to 3,000 fuel tanks per day. Portable LP gas fuel tanks, of the type commonly used for providing fuel for outdoor barbeque grills for example, similarly require periodic refilling from a large fixed or mobile storage tank. Large stationary LP gas fuel tanks, of the type commonly found outside rural residences that are not serviced by a natural gas utility, require periodic refilling from a mobile storage tank carried by a delivery truck.
At the present time, the most common means for filling fuel tanks or cylinders employs a screw connector wherein a threaded female coupling on a fuel hose is threaded onto a threaded male fitting mounted on the service valve of a fuel tank. Threading and unthreading a screw connector involves a great deal of time, and the repetitive action can promote operator injury, such as carpal tunnel syndrome.
Some quick connect fittings have been developed, but they have thus far been cumbersome and expensive.
An object of the present invention is to provide a quick connect fitting for connecting a fuel supply hose leading from a pressurized storage tank to a threaded fitting on a fuel tank that is simple and safe, preserves fuel, and maintains an appropriate level of sealing force over a range of operating conditions.